Page 50 - GIS for Science, Volume 3 Preview

The MoBI PWRSR map reconfirms some areas already recognized as conservation priorities, such as the California Floristic Province, Southeastern Coastal Plain, and Southern Appalachian Mountains. But the fine resolution of the input data and inclusion of an unprecedented diversity of taxa provides many novel insights. Smaller areas of ecological significance can be lost when continental prioritizations are revealed: the Edwards Plateau in Texas, the Lake Wales Ridge in Florida, the Ouachita Mountains of Arkansas, and the White Mountains of New Hampshire are just a few examples (Hamilton, Smyth, Young et al., in review). The results show that areas of biodiversity significance are often local in nature. the map was given a threshold, the map to identify the highest-scoring locations—places we call Areas of Unprotected Biodiversity Significance, or AUBIs, those locations were well dispersed across the country, occurring in almost every state.
Examining the results broken down by taxonomic groups helps reveal the drivers of the patterns observed, and can also help tailor effective conservation strategies. High scores on the Colorado Plateau and in California are driven largely by a great diversity of imperiled plants found in these topographically and ecologically diverse landscapes. High values in the Southeast are due in part to concentrations of imperiled freshwater species. Regional assessments consistently identify the southeastern United States as a hot spot of imperiled aquatic biodiversity (Elkins et al. 2019). But previous assessments have been based on species ranges mapped to watersheds, coarse geographic scales that are often challenging to translate into management and conservation actions on the ground. MoBI, for the first time, provides a fine-resolution picture of the freshwater reaches most critical for maintaining the globally significant freshwater biodiversity of the southeastern United States.
Areas of unprotected biodiversity importance, where modeled habitat for imperiled species falls outside GAP Status 1 & 2 protected areas. From Hamilton et al. (in review).
Anatomy of the PWRSR score
What does a PWRSR score mean on the ground? Consider a single 990-m pixel in the Texas Hill Country. At this location southwest of Austin, with a rapidly growing population and little land area set aside for biodiversity conservation, there is predicted habitat for six imperiled species, including the golden-cheeked warbler. All have 20% or less of their habitat overlapping current protected areas. The tricolored bat (Perimyotis subflavus) is found across the eastern United States and is imperiled primarily due to disease. Because of its large range, it contributes little to the PWRSR score at this (or any) location. But this pixel also contains habitat for four species found only in the limestone hills of south-central Texas. The critically imperiled bracted twistflower (Stepptanthus bracteatus) has already seen several populations lost to housing developments. The Jollyville Plateau salamander (Eurycea tonkawae) and Barton Springs salamander (Eurycea sosorum) have extremely small ranges. Their survival is threatened by urban development and groundwater depletion. The combination of small range sizes and lack of protection for these species leads to a high PWRSR score at this location.
Golden-cheeked warbler
Tricolored bat
Canyon mock orange
Bracted twistflower
Jollyville Plateau salamander
Barton Springs salamander
A view of the Texas Hill Country from a rural road in Hays County.
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